The present invention relates to a combustion heater.
The problem with many combustion heaters is that a high proportion of the heat generated in the combustion chamber is released into the atmosphere with flue gases. It is not unusual for flue gas temperatures for combustion heaters to exceed 1000 degrees fahrenheit. Attempts have been made to couple the combustion chamber of a heater with various types of heat exchangers. To date those attempts have been only partially successful, as the flue temperature remains relatively high.
What is required is a combustion heater which releases less heat to atmosphere with flue gases.
According to the present invention there is provided a combustion heater which includes a combustion chamber having a burner input port and a heat output port. A burner is coupled to the burner input port, whereby heat is generated within the combustion chamber. A heat exchanger is provided having an inlet and an outlet. The inlet is coupled to the heat output port of the combustion chamber. The heat exchanger consists of two hollow corrugated cones secured in base to base relation with opposed apexes.
The combustion heater, as described above, operates much more efficiently with a heat exchanger having the described corrugated heat exchanger configuration. The corrugations on the heat exchanger provide a large surface area over which a heat exchange may be effected. The corrugations are also able to accommodate thermal expansion, thereby permitting direct coupling to the combustion chamber.
The same factors which make the corrugated construction superior for the heat exchanger, make such corrugated construction superior for a combustion chamber. Although the combustion heater will operate with other types of combustion chamber, it is preferred that the combustion chamber consist of two hollow corrugated cones secured in base to base relation with opposed apexes.
Although beneficial results may be obtained through the use of the combustion heater, as described above, flue gas temperature may be closely controlled by selecting a secondary heat exchanger that is capable of extracting a desired proportion of the heat remaining when after the flue gas passes through the primary heat exchanger.
Although beneficial results may be obtained through the use of the combustion heater, as described above, to heat ambient air, it is preferred that the heat generated by capable of being controlled and directed for use where required. Even more beneficial results may, therefore, be obtained when the combustion chamber and heat exchanger are enclosed within a housing. The housing has an air circulation inlet and an air circulation outlet. A blower is provided to circulate air through the housing from the air circulation inlet to the air circulation outlet.